Background: - If I can recall,
the first true wideangle zoom lens that arguably broke the 28mm wideangle barrier
was a Zoom-Nikkor 25-50mm f/4.5 which actually was an attempt to extend the wideangle
from their earlier so-so effort of the Zoom Nikkor 28-45mm f/4.5 in 1975. Those days, it was true that high quality
zoom lenses were very difficult to produce, not to mention users were equally skeptical
in their confidence of using zoom lenses. In 1978, Canon had a breakthrough in designing
a high quality zoom with Aspherical lens element which was aimed to counter various
optical aberrations prohibiting designers in delivering a wideangle zoom of true
quality image delivery The FD 24-35mm f/3.5 ASPHS.S.C
(updated as Canon FD 24-35mm f/3.5L a year later in 1979 with new bayonet mount & lens
hood) was the first serious effort that surpassed Nikon effort (it was also the first
commercial production zoom lens for 35mm photography that incorporated with an Aspherical
glass element) but more importantly, it enabled Canon photographers to have an option
to tab on the convenience and enjoy high quality image resolution of a zoom lense.
I know probably most people would just associate Canon ultrawide Zoom with the modern
classic Canon FDn 20-35mm f/3.5L that followed in 1983 because along with a few other first
batch of the L-series FD lens group such as the Canon FDn 14mm f/2.8L,
FDn 50mm f/1.2LFDn 85mm f/1.2L
and some other renown FDn Telephotos, Canon FD lenses deservingly had the industry
recognized as not just the world's largest camera/optical lens producer - but also
a Company which leads and pioneering optical innovation and excellence. Amidst all
these development, the L-series lenses was aimed by Canon to supplement the professional
class Canon
New F-1 (1981) as well as
a whole new class of Canon T-Series camera models introduced during the first quarter of the eighties
to enable Canon seriously taking trying to wreck Nikon dominance at the professional
user market during the Nikon F3
era.

Canon FDn 24-35mm f/3.5L

Canon FDn 20-35mm f/3.5L

Minolta MD Rokkor 24-35mm
f/3.5

Pentax SMC 24-35mm
f/3.5

The design and manufacturing technique used
for the Canon FD 20-35mm f/3.5L has not just created an instance Canon Classic,
but it has given competitions such as Nikon, Minolta, Pentax having difficulties
a nightmare in finding workable solutions answering Canon's aggression; for an instance,
the first Nikkor 20-35mm was only being introduced as late as 1993 - more than a
decade behind Canon ! However, Pentax and Minolta reacted better than Nikon with
two pin-sized MD Rokkor and SMC 24-35mm f/3.5; however, both the lenses have not
been incorporated with an Aspherical glass element within and thus, confined themselves
as consumer class solution. Besides, when the 20-35mm FD zoom was introduced, there
was practically no competition in its class. Technically, you can also say the FDn
20-35mm f/3.5L was an evolved upgrade version for the earlier
24-35mm and it also formed the basis for the EF 20-35mm f/2.8L
which has been given a lens speed boost faster to f/2.8. For other third party lables,
try the EF
20-35mm f/3.5~4.5 USM secion

Since this section is not discussing
the version history, I will just provide a quite summary of various data:-

lens
type

Angle
of View

Optical
Design

optical
system

max/mim
aperture

closest
distance

filter
size

case(s)

lens
hood

Body
lengthapprox.

weight

year
introduced

FD 24-35mm f/3.5 S.S.C. ASPH

84° ~63°

12 elements 9 groups

Aspherical,
floating elements

f/3.5 ~ f/22

0.4m

72mm

LH B8 (hard);
LS A9 (soft)

W - 75

86.3mm

515g

(02.1978)

Canon FDn 24-35mm f/3.5L

84° ~63°

12 elements 9 groups

Aspherical,
floating elements

f/3.5 ~ f/22

0.4m

72mm

LH B8 (hard);
LS A9 (soft)

BW - 72

86.6mm

500g

(12.1979)

Canon FDn 20-35mm f/3.5L

94° ~63°

11 elements 11 groups

Aspherical,
floating elements

f/3.5 ~ f/22

0.5m

72mm

LH B8 (hard);
LS A9 (soft)

BW - 72

84.2mm

470g

(07.1983)

".... When the EOS system was announced
in 1987. The EF 20-35mm f/2.8L was among the original batch* of EF lenses that went to sale in order to boost confidence
of Canon photographers that Canon will commit to offer them the in both technologies
in camera as well as continual development of newer optics in the EF lens group.
The superwide served as a demonstration as it has significantly improved from many
aspect. While the EF 50mm f/1.0LUSM** and EF 85mm f/1.2L
USM lenses were created to reflect the potential of the fully electronic lens
mount of the EOS System, both the EF 20-35mm f/2.8L AFD and EF 80-200mm f/2.8L
AFD were partly responsible for the success of the original Canon EOS-1 in capturing
the lion's share in the professional 35mm SLR camera market..... - my "Captain Canon"
friend, Philip Chong -

*Introduced
at the same time with the camera were four new L-series
EF lenses, the EF 20-35mm f/2.8L AFD, EF 50mm f/1.0L USM*,
EF 85mm f/1.2L USM and the EF 80-200mm f/2.8L
AFD. ** Note Although formally introduced in 1987
with Canon
EOS 650 & EOS 620,
the EF 50mm f/1.0L USM was officially available for sale only from
Autumn 1989 onwards.

Firstly, the autofocus version of EF ultrawide
zoom has an entirely redesigned interface inside out. Optically, it comprised of
a new, rather complex 15 elements in 12 group optical arrangement and its constant
maximum aperture was fixed at f/2.8, brighter than the f/3.5 of the FD equivalent.

But basic principle remains, this 1.5:1
zoom ratio large-aperture super-wide-angle zoom lens covering all wide-angle focal
lengths from ultrawide 20mm to moderate wideangle of 35mm - offers the sharpness
and brightness of a single focal length lens via the use of a large-diameter ground
and polished aspherical lens for the front element virtually eliminates the distortion
common in wide-angle zooms. An internal focusing system with a floating effect ensures
rapid autofocusing and improves image quality at close shooting distances. Moreover,
the front of the lens does not rotate during focusing, facilitating use of circular
polarizing filters. All these provides a very well corrected geometry, flatness of
field as well as a very commendable close focus ability.

It used to be a high-quality zoom lens
highly praised by professional photographers worldwide. However, strangely USM was
not incorporated into the design and instead, it has a AFD (Arc Form Drive) actuator
which in a way prohibiting the use of full time manual focusing (the followed up
17-35mm EF-L in 1996 was USM enabled). The possible theory
was, since the wide angle has very narrow rotational drive from near to far and it
is not necessary to incorporate into the lens. Its moderate size (for a zoom lens
type such as this) and relatively light weight (510g) make this lens highly portable.
In fact, I think Canon designers have done an excellent job in this area despite
the fact, its 15 elements design and if you compared the previous (but mechanical)
FD version of maximum aperture of f/3.5; the f/2.8 and more number in elements does
not add more weight in the package.

If fast speed for low ambient light is not
entirely a must, a compromise of a f/2.8 should be adequate for most situation where
it carries the benefit of substituting a few prime wideangle lenses combined and
the aspherical front lens element assures superlative image quality comparable to
many prime optics. Personally, I think this lens is very practical for some serious
thought as companion for photojournalism, travels, nature, scenic and even for portraiture
as the varying angle of view presents many through the lens compositions without
the hassle of interchanging lenses for immediate assessment of visual effect. As
the lens has a non-rotational forward lens for internal zoom and focus control, it
facilitates the use of circular polarized filters (PL-C) filter
even at its widest angle of 20mm.

Yes. The seemingly evergreen users favorites
EF 20-35mm f/2.8L was officially retired from Canon EF lens group
in 1996 - it was barely few years after its nearest competition, Nikon caught up
with an equivalent of an Aspherical glass AF-Nikkor 20-35mm f/2.8D, Canon
thus, replied positively by announcing a worthy replacement optic for this long time
Canon classic with a Canon EF 17-35mm f/2.8L
USM; Five years later in Dec. 2001,
Canon went further ahead with a Canon EF 16-35mm f/2.8L (which is still current model)and
followed by another comparing alternative of EF 17-40mm f/2.8L in 2003 - in fact, the subsequent Canon EF lens group
has more options than any other manufacturers in the ultrawide zoom selection; alternatives
such as Canon EF 24-70mm f/2.8L USM, Canon EF 24-105mm f/4LIS USM and the earlier mentioned Canon EF 17-40mm
f/4L USM and EF 16-35mm f/2.8L USM. However, as most of the newer Canon L-series
Ultra Wides are relatively quite expensive even if it is used - as each may fetch
over USD1K+, an used 20-35mm f/2.8L can roughly quoted around + - USD450-00 becomes
very viable as serious consideration for many photographers.

In 1993, amidst all these development
on the EF lens group, the 20-odd years in the establishment of a hugely successful
20-35mm zoom range has maintained by Canon with an inclusion of an EF 20-35mm f/3.5-4.5
USM. This spherical optical ultrawide was also immensely popular as it carries with
a modest entry price tag and was very well received for users who may not be able
to afford the elite class of L-series EF superwide-zoom. You may consider go
through some basic reading references of other options below.

Special Credit:- :Mr. Richard Yeow & Mr. Simon Wong from camera division of Marketing Malaysia, for
their continual effort in supporting development of this EOS/EF website.Others: All
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brochures published by Nikon and/or contribution from surfers who claimed originality
of their own work for public publishing in this website, where majority of the extracted
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